Do not resort to all sorts of artificial nails and shellac; let your nails rest. Wearing synthetic materials for a long time and their constant correction lead to the thinning of nails.

In a salon, you can just increase and strengthen the nails that are initially in good condition and will keep gel or acrylic. Otherwise, it will only bring harm.

Finally, there are two unpleasant facts.

Firstly, widely advertised nail vitamins are practically useless. Nails are a dead tissue, like hair. The body sends all the nutrients (vitamins and minerals) to the organs that functionally need them, whereas nails get almost nothing.

Secondly, it is almost impossible to turn weak and thin by nature nails into firm and strong nails. Thickness and length of the nail root is genetically predetermined and cannot be changed. But if the naturally good nails have suddenly stopped growing and started to break down, you need to take action.